1. Field
One or more embodiments of the present invention relate to a secondary battery.
2. Description of the Related Art
Unlike a primary battery which is not designed to be rechargeable, a secondary battery is generally rechargeable and dischargeable. The secondary battery is used as an energy source of a mobile device, an electric vehicle, a hybrid vehicle, an electric bicycle, an uninterruptible power supply, etc., and according to the type of an external device using the secondary battery, the secondary battery may be used in the form of a single battery or in the form of a battery module obtained by connecting a plurality of secondary batteries in one unit.